cupstestppd: confusion about the "-R" option

[Kennedy, Smith (Macintosh Software - IPG MCT)]

Hello,

For whatever reason, I cannot seem to figure out how to get the "-R"  
option to work with cupstestppd, to have it look in an alternate  
root.  If I have a PPD named "foo.gz" that specifies a cupsFilter "/ 
usr/libexec/cups/filter/foofilter", and I have a local directory where  
I have built foofilter like so:

/home/smitty/build/usr/libexec/cups/filter/foofilter

then I was expecting that if I typed in this:

cupstestppd -R /home/smitty/build foo.gz

that it would prepend any paths found with "/home/smitty/build/" and  
search there.  But it doesn't seem to do that.  So how is this  
argument supposed to work?  It is never covered in the examples.

Thanks for any help,
Smith